Broccoli sprouts & sulforaphane: your best friends for detox

Broccoli and broccoli sprouts are superfoods – nutrient dense, full of fibre and antioxidants. In fact, the National Academy of Science cites that they contain the highest quantities of glucoraphanin, which when broken down becomes sulforaphane – a powerful antioxidant that is proven to protect your body from chemical toxins.

The transformation of glucoraphanin into sulforaphane is catalysed by another compound in broccoli, called myrosinase. Upon damage, like chewing, glucoraphanin and myrosinase create sulforaphane.

As a byproduct of this process, the plant releases chemicals which scientists have dubbed ‘the mustard oil bomb’. On an evolutionary level, it functions as the plant’s protective defence system against pathogens, fungi and insects. When we eat sprouts, the production of sulforaphane means we can defend ourselves from chronic illness caused by pollutants and oxidative stress.

Even if you don’t smoke, you’re exposed to chemical pollutants on a daily basis – alcohol, asbestos (common in Hong Kong buildings constructed before the 1980s), airborne toxins from pollution like benzene and acrolein, or aflatoxins, which are produced by mould species found in water damaged buildings – a characteristic which defines many of our dark, damp high-rises.

Detox involves three phases, and broccoli and its sprouts optimise all three to defend us from the impact of toxins. Just three serves of broccoli per week can have protective effects for your health.  

How sulforaphane supports detox

Sulforaphane protects against oxidative stress, which occurs when reactive oxygen species (ROS) outweigh your body’s ability to detox them using antioxidants.

ROS damage DNA and speed up the aging process. Oxidative stress is the underlying mechanism, contributing factor or accelerant of many chronic health conditions. It’s linked to depression, memory loss and chronic health conditions which affect the memory, heart, lungs, kidneys and joints.

Sulforaphane activates the Nrf2 pathway: the primary defence mechanism against ROS which reduces oxidative stress and governs the second phase of detox – a critical phase known as conjugation.

During phase I of detox, toxins are broken down into smaller, soluble compounds, which are often more reactive and damaging than the original form of the toxin. During phase II, the liver binds these broken-down toxins to other molecules, like antioxidants, making them less reactive, and easier for the body to excrete. Without phase II, super-toxic compounds remain in circulation in the bloodstream. Phase II is often neglected by fads like juice cleanses.

Safe and efficient detoxification involves a relatively slow phase I stage, followed by a rapid phase II stage, which prevents the accumulation of more toxic substances.

This is exactly what sulforaphane executes, as it slows down elements of phase I and upregulates phase II.

Sulforaphane stimulates the production of enzymes which are essential during the second phase of detox, including GSH (the active form of glutathione). One in seven phase II reactions conducted by the liver involves glutathione.

Other phase II enzymes include NQO1, GST (an enzyme which catalyses glutathione conjugation during phase II), HO-1 and TR (thioredoxin reductase).

All these enzymes function as antioxidants in their own right, neutralising ROS. HO-1 increases production of other antioxidants like bilirubin, which also help reduce ROS.  

These enzymes provide benefits over several days, rather than just a few hours – scientists suggest that vitamin C’s half-life is a mere 2 hours. This means that just 3 serves of broccoli a week (every few days) can have very protective effects, as demonstrated in hundreds of studies.

These enzymes are also able to return oxidised antioxidants to their active form. When antioxidants like thioredoxin neutralise ROS by donating their electrons they become oxidised (and no longer effective) in the process. Thioredoxin reductase returns the oxidised form to its active form, so it can continue doing its good work.

Through these actions, sulforaphane boosts detox and reduces oxidative stress, protecting organs like the eyes, kidneys, bladder and more from chronic illness.

Broccoli sprouts offer more optimised benefits for phases I and II– as mature broccoli contains compounds which stimulate both phase I and phase II, which is less ideal, but still good for us.

The benefits of broccoli don’t stop there – they continue to support phase III, as their fibre content supports regular, healthy bowel movement and removal of toxins from the body.

Broccoli is best 

While there are many crucifers (vegetables like cauliflower and kale) which can support detox, broccoli reigns supreme. Since 1997, there has been extensive research into the abilities of broccoli sprouts to protect against toxins. This body of research was led by Dr Jed Fahey, a nutrition biochemist.

His research demonstrated that 3 day old broccoli and cauliflower sprouts are shown to have 10-100 times higher levels of glucoraphanin than mature plants, offering more potent benefits in a much smaller quantity.

Scientists have also compared the ability of crucifers to induce phase II enzyme NQO1 – an important enzyme in the defence against toxins. Sulforaphane from broccoli returned ~33,000 units of NQO1 inducer activity per gram, compared to ~11,000 units from cabbage, ~10,000 units from kale and 2,000 units from turnip.

Defence against mould and air pollution

Researchers have found that when participants drank a broccoli sprout beverage, the rate at which they excreted benzene (an air pollutant) increased by 61% in the first day, which continued throughout the 12 weeks. The excretion of acrolein (another air pollutant) increased at a rapid and sustained rate of 23% throughout the experiment. Scientists noted that one of the possible mechanisms was the activation of NRF2, increasing the body’s defences against oxidative stress.

Scientists have also found that sulforaphane is able to increase phase II enzymes like glutathione, not only in the liver but also in the cells of the lungs – reducing the effects of oxidative stress on your airway. Similar benefits are gained with wasabi, or horseradish, both cabbage family plants high in sulforaphane which support nasal clearing and detox.

Studies on Chinese populations have also shown that broccoli sprouts can protect against the damaging effects of moulds like aflatoxins, which are a common mycotoxin in Hong Kong.

Broccoli sprouts protect your neurons

Sustained oxidative stress affects the brain significantly, causing  modification of proteins, lipids (which make up 78% of the brain’s composition) and nucleic acids, which make up DNA and RNA.

Your brain is sophisticated and demanding. The modifications caused by oxidative stress impair the function of brain cells – and the effect on neurons is particularly harmful, due to their high metabolic requirements.

Your neurons are also sensitive, and as they mature, they lose the ability to regenerate, so protecting them is key. Sulforaphane falls into the class of neuroprotective nutrients and studies have shown that it’s able to pass across the highly selective blood brain barrier.

Oxidative stress is a causative or contributing factor for many conditions which affect the brain. The antioxidant mechanism of sulforaphane provides potent benefits, and a large body of research proves this.

Sulforaphane has been shown to improve memory and cognitive function. By protecting brain cells – and specifically those that help produce dopamine, sulforaphane also supports better moods and focus. 

Broccoli sprouts for gut health

Oxidative stress is associated with constipation, and can lead to conditions like leaky gut. When the gut is affected, it’s often caused by seemingly innocuous medication like NSAIDs (ibuprofen), or bad bacteria in the gut.

When the gut experiences stress, it upregulates Nrf2 enzymes like HO-1, which reduce damage caused by NSAIDs and bad bacteria.

By assisting production of these enzymes, broccoli sprouts combat oxidative stress in the gut and support regular, healthy bowel movements.

The majority of our bacterial microbiome resides in the large intestine, and a healthy small intestine is home to much fewer numbers, in lower diversity. Colonisation of the small intestine can lead to digestive issues. Sulforaphane from broccoli sprouts helps prevent microbial invasion of the small intestine, maintaining a healthy balance of bacteria throughout your gut. Broccoli sprouts have also been shown to prevent the overgrowth of bad bacteria throughout your digestive tract. 

Your heart loves broccoli sprouts 

As well as being rich in sulforaphane, broccoli sprouts contain high levels of CoQ10, an antioxidant which supports better heart health. Studies show that broccoli sprouts have 3-8 times more CoQ10 than other kinds of sprouts.

A 2012 study on 81 patients demonstrated that when eating 10 grams of broccoli sprouts per day, people demonstrated a significant decrease in levels of triglycerides (fats) after the course of four weeks.

Research also shows that broccoli sprouts help you maintain a healthy heart rate.

How to eat broccoli for detox

In its raw form, broccoli contains myrosinase, an enzyme which breaks down glucoraphanin into sulforaphane. But, when cooked for longer than a four minute steam, levels of myrosinase decrease rapidly.

Pairing broccoli with myrosinase-rich sources of food like mustard, horseradish or wasabi can amplify the benefits of broccoli. The spicier the better. Root and seeds provide more benefit than a pre-prepared sauce.

If you’re not a fan of spice, radishes, cabbage, arugula, watercress and Brussels sprouts can help boost the production of sulforaphane when broccoli is consumed.

Sprouts can simply be eaten raw.

Once glucoraphanin is broken down by myrosinase to produce sulforaphane, it’s efficiently and rapidly absorbed by your small intestine and distributed throughout your body, providing benefits to all your body’s tissues and organs.

Vitamin D and sulforaphane work synergistically to amplify each other’s benefits, and both stimulate the Nrf2 pathway. So eating broccoli alongside a source of vitamin D, like oily fish or egg yolks can help support the process of detox.

In summary

Plant based antioxidants protect against illness. Sulforaphane and curcumin (an extract of turmeric) are the most powerful, as reported by a large body of evidence.

Boosting sulforaphane is particularly key during your later years, as Nrf2 activity suffers a decline in old age.

You can buy seeds and sprout your own broccoli at home, harvesting it every few days, or buy it in stores. Incorporating the mature plant into your diet more frequently also conveys benefits, though not as potently as their sprouts.

If you’d like personalised advice on how to create the right diet for your health concerns, I can help. I consider the complete picture of your symptoms and can assess your toxin levels, oxidative stress and any other associated issues using medical tests. Using your data, I personalise a treatment plan, including dietary recommendations to ensure you’re getting the nutrition you need to protect your health. 

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